This invention is directed to gelled hydrocarbon compositions prepared from partial aluminum salts of alkyl acid orthophosphates neutralized with polyamine compounds. More particularly this invention is directed to gelled hydrocarbon compositions comprising liquid hydrocarbons and gelling agents prepared from partial aluminum salts of alkyl acid orthophosphates neutralized with polyamines, which may further comprise uncured epoxy resins and amine curing agents for the epoxy component.
Partial aluminum salts of certain alkyl acid orthophosphates, when further neutralized with an inorganic base such as sodium hydroxide, ammonium hydroxide or the like, form pseudo double salts which are effective gelling agents. Hydrocarbon gels formed with these pseudo double salts are thixotropic, exhibiting high viscosity at rest and under low shear conditions and thus are capable of suspending large quantities of particulates such as sand without settling. These gels, even at very low concentrations, exhibit the ability to reduce fluid friction of hydrocarbons during high speed flow through pipes and orifices, decreasing the energy required to maintain fluid flow.
While these pseudo double salts have found a variety of applications where thixotropic gel properties and/or reductions in fluid friction are desired, their utility has been somewhat limited by a high degree of sensitivity both to alkalis and to acidic materials. The hydrocarbon gels are formed only at or very near a neutral pH, and the presence of excess base, or of acidic materials either prevents formation of a gel or quickly destroys the gels once they are formed. For that reason it has not been possible to employ these pseudo double salts to prepare gelled compositions containing as suspended or dissolved components such materials as epoxy resins with the commonly employed curatives. Additionally, the gels formed from the pseudo salts are thinned by heating, and after extended periods at elevated temperatures lose much of the gel character.